불꽃점화 엔진의 흡기관 분사를 위한 매립지가스 분사량의 측정 및 계산

김경수(Kyoungsu Kim),최경호(Kyungho Choi),전원일(Wonil Jeon),김바다(Bada Kim),이대엽(Daeyup Lee) 한국가스학회 2021 한국가스학회지 Vol.25 No.4

쓰레기 매립지에 발생하는 매립지가스(Landfill gas)를 대기 중으로 방출할 경우에 매립지가스에서 많은 부분을 차지하고 있는 지구온난화 지수(global warming potential)가 높은 메탄가스를 배출하게 되어 기후변화에 악영향을 주게 되고, 매립지가스에 함유되어 있는 메탄을 내연기관의 연료로 활용하여 연소하여 발전을 하게 되면 이산화탄소 형태로 대기 중으로 배출하게 되어 온난화 지수를 낮추는 데도 기여를 할 수 있게 된다. 따라서 매립지가스를 내연기관을 이용한 발전용 연료로 사용하기 위해서 엔진의 열효율을 높이는 것이 중요하기 때문에 기존의 믹서 방식 기술을 이용한 연료공급 방식보다는 실린더별로 흡기포트에서 전자 제어 인젝터를 이용하여 기체 분사를 하는 방식의 연료공급 시스템을 사용하는 것이 필요하게 된다. 따라서 전자 제어 기체 분사 방식 기술을 이용하기 위해서는 매립지가스의 사용 조건에 따른 질량 유량을 정확히 측정하는 것이 중요하게 된다. 이를 위하여 본 연구에서는 매립지가스를 기체 분사할 경우에 분사량을 측정 및 계산하는 연구를 수행하였다. When the landfill gas generated at the landfill site is released into the atmosphere, methane gas with a high global warming potential is emitted, which adversely affects climate change. When methane contained in landfill gas is used as fuel for internal combustion engines and burned to generate electricity, it is emitted into the atmosphere in the form of carbon dioxide, which can contribute to lowering the global warming potential. Therefore, in order to use the landfill gas as fuel for power generation using an internal combustion engine, it is important to increase the thermal efficiency of the engine. Thus, it is necessary to use a fuel supply system in which gas is injected using an electronically controlled injector at an intake port for each cylinder rather than a fuel supply technology using the conventional mixer technology. In order to use the electronically controlled gas injection method, it is important to accurately measure the mass flow rate according to the conditions of using landfill gas. For this, a study was conducted to measure the injection amount and calculate them in order for the intake port gas injection of landfill gas.

매립지가스 희박 연소 흡기관 분사 SI 엔진의 구성

김경수(Kyungsu Kim),최경호(Kyungho Choi),전원일(Wonil Jeon),신한길(Hangil Choi),이준호(Junho Lee),이대엽(Daeyup Lee) 한국가스학회 2020 한국가스학회 학술대회논문집 Vol.2020 No.10

쓰레기 매립지에 발생하는 매립지 가스(Landfill gas)를 대기중으로 방출할 경우에 지구온난화지수(global warming potential)가 높은 메탄가스의 배출로 인하여 기후변화의 악화를 초래하게 된다. 매립지 가스에 함유 되어 있는 메탄을 내연기관의 연료로 활용하여 발전을 하고 이산화탄소 형태로 배출하여 기존 전력 생산에서 발생하는 이산화탄소도 대체하게 되면 온난화지수를 낮추는데 기여할 수 있게 된다. 매립지가스를 내연기관을 이용한 발전용 연료로 사용하기 위해서는 엔진의 열효율을 높이는 것이 중요하기 때문에 기존의 믹서를 이용한 연료 공급 방식보다는 실린더별로 흡기포트에서 전자 제어 인젝터를 이용하여 기체 분사를 하는 방식의 연료공급 시스템을 사용할 수 있도록 엔진을 구성하였다. 전자 제어 기체 분사 연료를 하게 되면 매립지가스의 연료 성분의 변화에 따른 에너지 변동 및 이에 따른 부하 변동 발생에 따른 엔진의 출력 제어 특성도 좋아지게 되어 발전의 품질도 향상이 되게 된다. 매립지가스를 희박연소 조건에서 점화를 하기 위해서는 이론 공연비 혼합기의 점화보다는 더 높은 점화 에너지가 필요하게 되어 점화 에너지 향상을 위한 연구도 중요하다. 이를 위하여 본 연구에서는 매립지가스를 희박연소하는 점화착화 엔진의 구성 연구를 수행하였다. In case that landfill gas generated at landfill sites is released into the atmosphere, climate change becomes worse due to the emission of methane gas with a high global warming potential. If the methane contained in the landfill gas is used as energy for the internal combustion engine to generate electricity and is discharged in the form of carbon dioxide, which may replace the carbon dioxide generated from normal electricity generation, it can contribute to lower the global warming potential. In order to use landfill gas as a fuel for power generation using an internal combustion engine, it is important to increase the thermal efficiency of the engine. Thus , it is better to use gas injection with electronically controlled injector at the intake port for each cylinder rather than the conventional fuel supply method using a mixer. When a fuel supply system with electronically controlled gaseous injection is used, energy fluctuations due to changes in fuel components of the landfill gas and consequently control characteristics according to load fluctuations accordingly are improved. In order to ignite the landfill gas under lean burn conditions, higher ignition energy than the spark ignition of the theoretical air-fuel ratio mixture is required, thus spark ignition system for a higher ignition energy is also important. For this, in this study, a study on the construction of an spark ignition engine that is fueled by landfill gas was conducted.

대전광역시 음식물류폐기물 바이오가스화의 전과정평가 연구

Yashoda Padeyanda,고영재,장용철 한국폐기물자원순환학회 2015 한국폐기물자원순환학회지 Vol.32 No.1

This study was initiated to examine the potential impacts on the environment during the management of food waste by anaerobic digestion in Daejeon Metropolitan City (DMC) that is built in 2017. The evaluation was based on both material flow analysis (MFA) and life cycle assessment (LCA). The MFA study was performed using STAN 2.5, while the LCA was conducted according to ISO standards by utilizing Total 4 LCA software with the incorporation of CML 2002 methodology. According to the LCA results, global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), and photochemical ozone creation potential (POCP) were found to be approximately 166 kg CO2-eq/ton of food waste, 0.43 kg SO2-eq/ton of food waste, 0.66 kg PO4 3−eq/ton of food waste, and 0.08 kg C2H4-eq/ ton of food waste, respectively. The disposal stage showed higher impact of GWP on the environment due to the landfilling of solid sludge and screening waste. In case of eutrophication potential, the treatment phase showed the highest impact on the environment, mainly because of the consumption of electricity. Based on the results of normalization, the highest environmental impacts was found in the treatment stage related to eutrophication potential. The results of LCA would provide policy-makers to identify and reduce potential environmental impacts associated with food waste to biogas conversion in DMC by life cycle.

A2L R32 냉매 특성과 성능 평가

고영환(Young Hwan Ko),최득관(Deuk Gwan Choi),오세기(Sai Kee Oh) 대한설비공학회 2018 대한설비공학회 학술발표대회논문집 Vol.2018 No.11

신냉매 개발 현황 및 규격 동향

고영환(Younghwan Ko),오세기(Saikee Oh),김병순(Byungsoon Kim) 대한설비공학회 2019 대한설비공학회 학술발표대회논문집 Vol.2019 No.-

Along with international regulatory action to protect the global environment, the refrigeration and air conditioning industry has been challenged continuously to curb the use of fluoridated greenhouse gases. With the signing of 197 countries in the October 2016 Kigali Amendment, legal regulatory policies for F-gas reduction are accelerating. EU countries are introducing F-gas quota system to strengthen environmental regulations on HFCs, which have a significant impact on global warming. These regulations are affecting domestic refrigerators, heat pump dryers and airconditioners in which HCFC & HFC refrigerants were used. And It is directly weakens productive competitiveness in the international market. Currently, other advanced countries such as EU and USA are taking the lead in the global refrigerant regulations. They are stepping up new alternative refrigerants and some of them are already available in the market. We also have to understand these new directions about Global warming and refrigerant, and need to prepare before it is too late. Therefore, I would like to introduce recent trends of refrigerant regulation&polish in different countries.

연구논문 : 태양에너지 가용잠재량 자원지도 분석

정종철 ( Jong Chul Jeong ) 한국환경영향평가학회 2012 환경영향평가 Vol.21 No.4

Many countries have recently been expanding efforts for low-carbon global economy to solve the problem of global warming. Development and research for various types of new reusable energy is on the rise throughout the world, The most promising source of energy is the solar photovoltaic energy and the government take an initiative to establish both short-term and long-term policies to develop the solar energy potential resource map, The solar energy and industrialize area researched by GIS methods for optimum site for solar power transfer system. This study attempts to address the hot issue of the development and suitability of the solar photovoltaic energy site using GIS spatial analysis. We need to analyze and describe the solar technology, green energy policies and the energy market trend of the field.

논에서 SRI 물관리 방법에 의한 온실가스와 관개용수 저감효과 분석

서지연,박배경,박운지,이수인,최용훈,신민환,최중대 한국농공학회 2018 한국농공학회논문집 Vol.60 No.1

Water management impacts both methane (CH4) and nitrous oxide (N2O) emissions from rice paddy fields. Although irrigation is one of the most important methods for reducing CH4 emission in rice production systems it can also N2O emissions and reduce crop yields. A feasibility study on the system of rice intensification (SRI) methods with respect to irrigation requirements, greenhouse gas (GHG) emissions was conducted for either 2 or 3 years depending on the treatment in Korea. The SRI methods (i.e. SRI and midsummer drainage (MD) with conventional practice (CT)) reduced the irrigation requirement by 49.0 and 22.0 %, respectively. Global warming contribution of GHG to different depending on the type of GHG. Therefore, the emission of CH4 and N2O shall be converted to Global Warming Potential (GWP). The GHG emission from the conventional practice with midsummer drainage (MD) and the SRI plots, in GWP were reduced by 49.1 and 77.1 %, respectively. Application of SRI water management method could help to improve Korea’s water resources and could thus contribute to mitigation of the negative effects of global warming.

Numerical Analysis on the Thermal Decomposition of the HFC-134a Refrigerants

Yongguk Lee,Yongju Kim,Dongsoon Jang,Misoo Shin 한국폐기물자원순환학회 2015 한국폐기물자원순환학회 학술대회 Vol.2015 No.05

Proper management of refrigerant mixtures containing chlorine and fluorine are gaining worldwide interest in the recent years as, they contribute to global warming and ozone depletion. according to the Montreal Protocol, developed nations have substituted HCFCs in refrigerators and air conditions synthetic greenhouse gas (SGGs) refrigerants such as, R-10 (CCl4), R-23 (CHF3), and R-134a (CH2FCF3). SGGs contribute to the increasing global warming potential. incineration, conventional treatment method of R-134a leads generation of Freon gas, due to excess air during the deacon reaction and due to the flame inhibition of the halogen compound. Therefore, this study proposes on the effective thermal treatment (high-temperature pyrolysis) of R-134a using numerical analysis. R-134a is usually known to have reaction characteristics which degrade only at temperatures reaches 800℃ and contains sufficient moisture in the furnace, HFC-134a refrigerant is treated efficiently by following chemical reaction. C2H2F4+4H2O → 4HF+3H2+3CO2, 4HF+2Ca(OH)2 → 2CaF2+4H2O in this study numerical calculation is performed for the relevant variables. As a result, very positive preliminary results showed about HFC-134a refrigerant treatment. Base on this, in the following study, organized variable research and demonstration experiment will be performed.

Numerical Analysis on the Thermal Decomposition of the HFC-134a Refrigerants

( Yongguk Lee ),( Yongju Kim ),( Dongsoon Jang ),( Misoo Shin ) 한국폐기물자원순환학회(구 한국폐기물학회) 2015 한국폐기물자원순환학회 춘계학술발표논문집 Vol.2015 No.-

Proper management of refrigerant mixtures containing chlorine and fluorine are gaining worldwide interest in the recent years as, they contribute to global warming and ozone depletion. according to the Montreal Protocol, developed nations have substituted HCFCs in refrigerators and air conditions synthetic greenhouse gas (SGGs) refrigerants such as, R-10 (CCl₄), R-23 (CHF₃), and R-134a (CH₂FCF₃). SGGs contribute to the increasing global warming potential. incineration, conventional treatment method of R-134a leads generation of Freon gas, due to excess air during the deacon reaction and due to the flame inhibition of the halogen compound. Therefore, this study proposes on the effective thermal treatment (high-temperature pyrolysis) of R-134a using numerical analysis. R-134a is usually known to have reaction characteristics which degrade only at temperatures reaches 800℃ and contains sufficient moisture in the furnace, HFC- 134a refrigerant is treated efficiently by following chemical reaction. C₂H₂F₄ + 4H₂O → 4HF + 3H₂ + 2CO₂, 4HF + 2Ca(OH)₂ → 2CaF₂ + 4H₂O in this study numerical calculation is performed for the relevant variables. As a result, very positive preliminary results showed about HFC-134a refrigerant treatment. Base on this, in the following study, organized variable research and demonstration experiment will be performed.

EXPERIMENTAL STUDY ON PERFORMANCE OF AUTOMOTIVE AIR CONDITIONING SYSTEM USING R-152a REFRIGERANT

유성연,이대웅 한국자동차공학회 2009 International journal of automotive technology Vol.10 No.3

Recently, as climate changes have manifested worldwide, every country is making efforts to prevent ozone depletion and global warming. In the automotive industry, R-134a refrigerant is widely used in air conditioning systems because it has zero ozone depletion potential (ODP). Unfortunately, its global warming potential (GWP) is high. Therefore, alternative refrigerants are needed as a replacement for R-134a. R-152a is considered to be one of the better alternative refrigerants due to zero ODP and low GWP. In this paper, the performance of an automotive air conditioning system using R-134a and one using R-152a are compared experimentally at the bench level. The experimental apparatus simulated a real automotive air conditioning system consisting of a cabin and engine room structure. The cooling capacity, condensing capacity, coefficient of performance (COP) and power consumption characteristics of the automotive air conditioning system are evaluated by changing the air velocity entering the condenser and the compressor rotation speed with the optimized refrigerant charge amount. Also, the performance of the R-152a system was investigated by changing the thermostatic expansion valve which is set of values. The results of this study show that the R-152a system is slightly better than the R-134a system, not only under driving conditions but also under idling condition. R-152a refrigerant thus shows promise as an alternative refrigerant to replace the current standard, R-134a, in automotive air conditioning systems.